Driving mechanism for hand-drills



(No Model.)

J. W. KNAPP. DRIVlNG MECHANISM FOR HAND DRILLS.

Patented Mar. 3, 1891.

AUOR/VEYS UNITED STATES JONAII IV. KNAPP, OF CROSS RIVER, NEV YORK.

DRIVING MECHANISM FOR HAND-DRILLS.

SPECIFICATION forming part of Letters Patent No. .1;4'1614,dated March 3, 1891.

Application filed September 25, 1890. $erial No. 366,106. (No model.)

I Cross River, in the county of lVestchester and Improved Driving Mechanism for Hand:

Drills, of which the following is a full, clear, and exact description.

My invention relates to an improved driving mechanism for hand-drills, and has for its object to provide a simple and economic attachment for drills whereby the instrument may be effectually driven at a high rate of speed, and while driven be conveniently manipulated to operate upon the upper face, the sides, or bottom of objects, whether the objects be upon, above, or below a bench or other support, and whereby, also, the instrument will'work equally well when in a horizontal position orin a vertical position facing upward or downward, or in any position intermediate of the said points.

The invention consists in the novel construction and combination of the several parts, as will be hereinafter fully set forth, and pointed out in theclaims.

Reference is to be had to the accompanying drawings, forming apart of this specification, in which similar figures and letters of reference indicate correspondingparts in all the views.

Figure 1 is a side elevation of the drill and attached driving mechanism. Fig. 2 is a plan view of the drill. Fig. 3 is an enlarged side elevation of the drill, and Fig. 4 is an enlarged rear elet ation thereof.

The drill A may be of any suitable or approved construction, consist-ing primarily of a body-casing and a shaft 11, held to revolve in the casing, threaded at its lower end toreceive a chuck 12, the upper end of the shaft having secured thereto a horizontal peripherally-grooved pulley 13. At the upper end of the casing 10 of the drill a horizontal bracket let is rigidly fastened, which bracket extends beyond one side face of the body-casing, and is provided with a vertical member 15. In the member of the bracket four peripherally-grooved pulleys 16 are journaled, the said pulleys being journaled in pairs, one pair immediately beneath the other, and the pairs approach each other as closely as possible without being in actual contact. The horizontal pulley 13 is so located that it is opposite the space intervening the pairs of pulleys 16. The pulleys 16, it will be understood, are at a right angle to the horizontal pulley 13. t

The brackets and pulleys constitute one portion of the drivingmechanism of the drill. The other portion of the driving mechanism is best shown in Fig. 1, in which a drivingpulley 17 is shown as journaled beneath a table 18, the said pulley being adapted to be hand or by means of a motor. The table 18, preferably at its rear edge and over the pulley 17, is provided with an idler, .or guide pulley 19.

Over the rear end of the bench or table 18 a pulley 20 is suspended from the ceiling or from any equivalent overhead ,support. A cord, rope, or chain 21 is passed over the pulley 20, one endv of the cord having attached thereto a weight 22, the other end of the cord being secured to the upper end of a spring 23, preferably a spiral or coil spring. The lower end of the spring is attached to the frame 2a of two pulleys 25 and 26, one being located above the other, and a drivingbelt 27, which is endless, is made to pass over the driving-pulley 17, one of the members of 19, while one member of the belt is also passed over the pulley 26 and the other overthe pulley 25. The two members of the belt are thence passed downward in engagement, with the pairs of pulleys 16 of the drill, passing be- 4, and finally the belt is carried around the horizontal pulley 13, attached to the main shaft 11 of the drill.

A guide-rod 28 is secured to the ceiling or other support at one end, and is passed downward through the spring 23, the lower end of the rod being secured permanently to the in proper alignment with the driving-pulley 17 at all times, thus effectually preventing the belt from slipping when the drill is manipulated in use.

The amount of tension exerted upon the rotated in any approved manner, either by the belt being in engagement withthe idler tween said pairs, as illustrated in Figs. 3 and table 18 or equivalent support. The object of the rod 28 is to preserve the pulleys 25 and 26 a pulleys 16 ot' the drill when it is manipulated is regulated by the heft of the weight E32as, for instance, it the weight is a five-pound weight, after five pounds pressure has been exerted upon the drill in drawing it downward (within reach of the table, for instance, or below it) the spring 23 will have been extended as far as possible, and this amountot pressure will be constantly upon the drill, no matter how much lower or farther away the drill is taken, as the weight 22 will pass upward, being itself a counter-balance to the spring 23.

It will be readily observed that by passing the endless belt 27 through the two pairs of pulleys 16, and thence over the horizontal pulley 13, no matter in what position the drill is held the belt will engage with at least two of the pulleys 16 and the horizontal pulley 13. Thus the shaft 11 of the drill is constantly and uninterruptedly revolved as soon as power is applied to the pulley 17. For instance, it the drill is held in the normal position shown in Fig. 1--that is, with the chuck pointing down wardthe driving-belt will engage with the upper set of pulleys l6, and if the position of the drill is reversed the drivin g-belt will engage with the lower set of 'pulleys. If the drill is held horizontally, the driving-belt will engage with the upper or lower set of pulleys, according to the angle at which the drill is placed with respect to a perpendicular line.

The driving mechanism of the drill is ex ceedinglysimple and durable, and it is evident that it may be applied to drills of any description, the drill illustrated in the drawings being a jewelers tool; but the drill may be a dental one, or it may be an ordinary drill for working metal or wood.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. The combination, with a drill provided with a pulley horizontally attached to its main stem or shaft, of pulleys supported in pairs at one side of the horizontal pulley, substantially as and for the purpose specified.

2. The combination, with a drill provided with a pulley horizontally secured to its driving shaft or stem, of a bracket connected with the drill, pulleys arranged in pairs and journaled in the said brackets, located opposite one side of the horizontal pulley, and a drivin g-belt passed between the pairs of pulleys and over the horizontal pulley, substantially as and for the purpose specified.

3. A drill provided with a horizontal pulley attached to its driving shaft or stem, and vertical pulleys arranged in pairs located at one side of the horizontal pulley, the said horizontal pulley being in alignment with the space intervening the peripheral surface of the pairs of pulleys, substantially as shown and described.

t. In a driving mechanism, the combination, with a driving-pulley, an upper pulley, and a cord passed over the upper pulley having a spring attached to one end and a weight secured to the other, of guide-pulleys secured to the lower end of the spring, and a drivingbelt passed over the driving-pulleyand guide pulleys, substantially as shown and described.

5. In a driving mechanism, the combination, with a driving-pulley, a pulley located above the same, a cord passed over the upper pulley and provided at one end with an at tached spring and at the other end with an attached weight, of guide-pulleys connected with the lower end of the spring, a guide-rod passed through the spring, and a driving-belt engaging with the driving-pulley and guidepulleys, substantially as and for the purpose specified.

6. The combination, with a drill having a horizontal pulley secured to its driving shaft or stem and vertical pulleys arranged in pairs at one side of the horizontal pulley, of a driving-pulley, a suspension-pulley, a rope or cord passed over the suspension-pulley, a spring secured to one end of the rope or cord and a weight attached to the other end, guide-pulleys secured to the lower end of the spring, and a driving-belt engaging with the driving-pulley, the guide-pulleys, and the horizontal pulley of the drill, the said belt passing between and engaging wit-h the vertical pairs of pulleys, as and for the purpose specitied.

JON-All \V. KNAPP.

Witnesses:

\VASHINGTON '1. Roimixn, Wit. T. FORD. 

